I have a screenshot attached. Whether trying to build any output version I am running into this popup error. Since I have no way to observe the symbols in this library and none are loaded. I was wondering if this could be a corrupt download of the external.zip archive.

Another possibility is that Wesnoth may load some DLL from a wrong place, and such a DLL may expect SDL2_ttf.dll to provide InterlockedCompareExchange(). Although that doesn't seem to be the cause according to your log.

Edit: a good way to get Wesnoth to load the DLLs from a right place is to add external\dll to the beginning of the PATH variable, not to the end.

I downloaded externalvc14 and have the path set correctly. If with Boost Libraries, The external dependencies and VS2015 meeting the requirements. I will try to use the download version of wesnoth and copy over the SDL libraries. That probably would be the most logical way to establish a proper methodology. If not then I am stuck due to the fact I have had many wild issues with SDL compiling and they are never ending. Let me see if this works. Thanks all for the support.

Thanks for posting the version number of the exe. Just copying that SDL2_tff.dll to the external directtories solved the issue. wesnoth is up and running now in debug mode moving rather quickly. Thanks!!